The present invention relates to a method for linear guidance of motion of limited extent in a preselected direction of a device that is operating in the imaging beam of a camera in relation to a reference system at the camera. The invention relates further to an arrangement for guidance of such a movement.
The invention is based on problems that develop in the area of the digital camera technology, particularly that of the digital still camera technology, and especially in the area of the multi-shot technology thereof.
Basically in multi-shot technology, the matrix of optoelectric transducer elements commonly called pixel matrix, for instance a CCD area chip, is shifted two or more times in the imaging beam path and several images are registered by triggering a respective partial image storage. These are processed into an unitary image result. Thereby one makes sure that at each image point of the image beam, all the selective transducer elements become effective, usually selective on the three primary colors. It is therefore necessary that the pixel matrix is shifted sequentially relative to the imaging beam and sequential partial images are registered, respectively. It is of crucial importance for the quality of the resulting image that the mentioned pixel matrix shift occurs in a highly precise and precisely repeatable manner, which applies to the displacement amount as well as to the displacement direction.
With respect to said multi-shot technology, I refer to the technical information brochure from RODENSTOCK Prazisionsoptik GmbH, Isartalstr. 43, D-80469 Munich, Germany, 4/99 W. E. Schön 9543 512 1512 (English) or 9543 512 1511 (German) having the title “Digitale Fotografie und ihre Ansprüche an das Aufnahmeobjectiv” or (in English) “Digital photography and its demands on the taking lens,” with particular reference to the section “Another ingenious trick: scanning with the CCD area array for even better image quality.”
This technical background information is intended to be an integral part of the present description.
From this technical area, the present invention focuses basically on the precise direction guidance of the transducer matrix in the imaging beam of a digital still camera. The invention specifically takes up the task to provide a method or an arrangement by which means a transducer-matrix movement guidance is made possible which is                highly precise        simple in construction and with low expenditures        resistant to wear and abrasion.        
By means of the following specified inventive solution of the problem of movement guidance in the specific context mentioned above, a movement guidance method or a corresponding arrangement is basically created that is deployable in any case where it is necessary to realize precise movement of a device operating in the imaging beam of a camera. This may also be, for example, the movement of a color filter matrix.
The stated object is achieved by a method of the kind as mentioned above in that the device is moved at least with a movement component in the preset direction and whereby the exclusiveness of the movement in said direction is ensured by a bending connection of the device relative to the reference system, about swiveling axes that are parallel to each other and perpendicular to said direction.
For realization of the inventive, desired precise linear movement guidance there is this not realized a translatory guidance in the desired direction but, according to the invention, precise guidance is guaranteed by swivel bearings. Thereby there is achieved on one hand the required high guidance precision and translatory guidances are not used on the other hand, as for example ball bearing guidances, etc. Thereby also the other requirements are totally fulfilled according to the invention in terms of simplicity in construction, minimum clearance, and resistance to wear and abrasion.
Whenever said device, specifically a matrix of optoelectric transducers, is not only to be guided precisely and linearly in one preset direction—independent whether the movement drive operates precisely only in said direction or whether it produces additional drive components in a perpendicular direction thereof but is to be guided along two mutually perpendicular of such preset directions (in the sense of a X-Y stage guidance), then two of said bending connections are provided, which swiveling axes being respectively perpendicular to one of said directions. Thereby the device may be moved in any direction in one plane—as in an X-Y stage. Concerning the drive (force) in the particular directions, there is the fact that only and exclusively the drive components become effective in the particular preset directions. Thereby precise and reproducible movement control is made possible, within limits independent from the fact whether the direction-specific preset drives create additional drive components or not—in addition to drive components in the said preset direction. It is not imperative but it is preferred that the guided directions are mutually perpendicular as in a common X-Y stage guidance. They are more generally warped at an angle and so are the particular swiveling axes therefore.
The inventive method is preferably deployed in a digital camera, particularly a digital still camera, especially for guiding of an optoelectric transducer array, preferably a CCD or CMOS image sensor array in the imaging beam. This is especially deployed for the movement of the transducer array in the multi-shot technology.
As a solution to the stated task according to the invention, the arrangement of the type as mentioned in above is characterized by the fact that                a coupling arrangement is provided for a drive between the reference system and the device,        a plane movement guide for the device is provided,        a hinge connection to the device that has at least three swiveling axes, which are spaced apart and are parallel to one another, and which lie parallel to said plane.        
As an example, the invention is described below with reference to drawings.